Error: undefined symbol: zend_open

You can check the status with:
php -v

If the output looks like this:
Failed loading /usr/local/Zend/lib/Optimizer-2_6_2/php-4.3.x/ZendOptimizer.so: /usr/local/Zend/lib/Optimizer-2_6_2/php-4.3.x/ZendOptimizer.so: undefined symbol: zend_open

Just grab an old version that works:
http://downloads.zend.com/optimizer/2.5.7/

SQL Fetch Size

Statement and ResultSet: get/setFetchSize

Exit value

ls -l
EXITVALUE=$?
if [ $EXITVALUE != 0 ]; then
echo "Exit value was [$EXITVALUE]"
fi
exit 0

QNX

Again, with QNX.

MySQL Dump

Dump / Export
mysqldump --opt --user=dbuser --password dbname > db.dmp.sql

Load / Import
mysql --user=dbuser --password dbname < db.dmp.sql